1. Field of the Invention
The present invention relates generally to winches and pulleys, and more specifically to a winch pulley accessory which is used with a motor vehicle-mounted winch and box hitch to pull the vehicle in a desired direction.
2. Description of Related Art
Motor vehicles, particularly those traveling off-road, often get bogged down in mud, snow, ditches and the like. Since four-wheel-drive vehicles are frequently used off-road, they are particularly prone to getting stuck. If such an incident occurs in a remote area, such as on a hunting trip, help may be unavailable. For this reason many four-wheel-drive vehicles have an attached winch. The winch can be attached to a convenient fixed object, such as a tree, and used to pull the vehicle to better ground or back on a road.
Most vehicle-mounted winches are electrical, as pulling a heavy truck out of muck is very difficult work with a mechanical winch. Most electrical winches are mounted on the front of the vehicle. This position gives easier access to the vehicle's electrical system, reducing the expense of installation. A front-mounted winch also does not interfere with moving cargo in and out of the rear. Electrical winches are available which can be either front-mounted or rear-mounted, but such winches tend to be more expensive and heavier than conventional winches and require extra wiring.
A conventional front-mounted winch can only pull the vehicle forward. Attempting to pull a vehicle backwards or sideways with a conventional front-mounted winch leads to the winch cable bending at sharp angles where it contacts the vehicle body or frame. At best the winch jams and/or damages the vehicle; at worst the winch cable breaks. A front-mounted winch will operate properly only when pulling toward a fixed object within a fairly narrow range of pulling angles toward the front. This can be very inconvenient when no fixed objects are available in suitable positions, or when the best way out is backwards or sideways.
Unfortunately, vehicles typically get into trouble front first, so that the best way out most often is backwards or sideways. For example, a truck stuck with its front wheels in a roadside ditch is not likely to get back on the road by being pulled forward.
The teachings of related art patents will now be discussed in detail.
U.S. Pat. No. 5,593,139 by Julian discloses a device for connecting a winch to a box hitch in various orientations. This device is capable of pulling a vehicle in various directions. However, the device involves attaching a winch to the end of a long tubular member attached to the box hitch. Use requires lifting the full weight of the winch, in addition to the weight of the connector. The winch-connector combination is bulky and awkward to transport. The winch can be easily damaged if the combination is allowed to roll around during transport.
Julian's device cannot be used at all with the conventional front-mounted electrical winch typically found on four-wheel-drive vehicles. Julian's device requires a portable winch to be attached to the connector. Any electrical winch used with Julian's device would have to be connected to the vehicle engine by wiring extending the full length of the tubular member. The connection would have to be either detachable or fabricated on the spot. Either type of connection would be easily damaged in use. Making the connection would require time and would be very difficult in bad weather or at night. Due to these difficulties, Julian's approach is practical only with a mechanical winch.
U.S. Pat. No. 2,470,242 to Felsing discloses a lift attachment for trailer drawbars having a winch-like device driven by a worm gear. U.S. Pat. No. 2,490,772 to Benner shows a fork lift truck which can be converted into a crane by an adapter mounting a first pulley to the forks, a second pulley to the top of the uprights, and a winch mounted on the rear of the truck, the winch cable being routed under the truck, over the second pulley, and down over the first pulley. The device is for lifting objects, not pulling the fork lift truck laterally.
U.S. Pat. No. 2,120,637, issued Jun. 14, 1938 to H. J. Van Doorne, shows a coupler for attaching ordnance to the rear of a tractor which includes a winch whose cable is guided over pulleys. The coupler permits the load to be taken off the winch cable while relocating the tractor without disconnecting the draw hook, and does not redirect the pulling direction of the winch.
U.S. Pat. No. 4,238,116, issued Dec. 9, 1980 to Plante, et al., teaches a device for pulling logging tractors, known as skidders, out of ruts. The skidder is normally equipped with a winch in the rear having a winch idler pulley. The device includes front and rear jacks having a plurality of horizontally and vertically oriented rollers. The skidder may be pulled forward by routing the winch cable over the idler pulley, under one of the horizontal rollers in the rear jack, under the skidder, under the horizontal roller in the front jack, and tying the cable around a tree. The vertical rollers help if the tree is at an angle.
With regard to the device in Plante, it is noted that (1) the winch is mounted in the rear of the vehicle; (2) the device depends upon a winch idler pulley mounted on a boom type crane; (3) the rollers have no groove to guide the cable, so that there is a possibility that the winch cable may become wedged between the horizontal and vertical rollers during the pulling operation; and (4) the device is not designed for pulling the skidder sideways, the vertical rollers being of smaller diameter; and (5) the jacks are not adapted for mounting on cars, pickup trucks, and other conventional vehicles.
Less relevant are devices which adapt the drive wheels of the vehicle to serve as a winch, such as those described in U.S. Pat. No. 4,778,126, issued Oct. 18, 1988 to C. D. Spann, Jr., and U.S. Pat. No. 5,054,745, issued Oct. 8, 1991 to Swayze, et al.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.